/*
** $Id: lobject.h,v 2.117.1.1 2017/04/19 17:39:34 roberto Exp $
** Type definitions for Lua objects
** See Copyright Notice in lua.h
*/

#ifndef lobject_h
#define lobject_h

#include <stdarg.h>

#include "llimits.h"
#include "lua.h"

/*
** Extra tags for non-values
*/
#define LUA_TPROTO LUA_NUMTAGS         /* function prototypes */
#define LUA_TDEADKEY (LUA_NUMTAGS + 1) /* removed keys in tables */

/*
** number of all possible tags (including LUA_TNONE but excluding DEADKEY)
*/
#define LUA_TOTALTAGS (LUA_TPROTO + 2)

/*
** tags for Tagged Values have the following use of bits:
** bits 0-3: actual tag (a LUA_T* value)
** bits 4-5: variant bits
** bit 6: whether value is collectable
*/

/*
** LUA_TFUNCTION variants:
** 0 - Lua function
** 1 - light C function
** 2 - regular C function (closure)
*/

/* Variant tags for functions */
#define LUA_TLCL (LUA_TFUNCTION | (0 << 4)) /* Lua closure */
#define LUA_TLCF (LUA_TFUNCTION | (1 << 4)) /* light C function */
#define LUA_TCCL (LUA_TFUNCTION | (2 << 4)) /* C closure */

/* Variant tags for strings */
#define LUA_TSHRSTR (LUA_TSTRING | (0 << 4)) /* short strings */
#define LUA_TLNGSTR (LUA_TSTRING | (1 << 4)) /* long strings */

/* Variant tags for numbers */
#define LUA_TNUMFLT (LUA_TNUMBER | (0 << 4)) /* float numbers */
#define LUA_TNUMINT (LUA_TNUMBER | (1 << 4)) /* integer numbers */

/* Bit mark for collectable types */
#define BIT_ISCOLLECTABLE (1 << 6)

/* mark a tag as collectable */
#define ctb(t) ((t) | BIT_ISCOLLECTABLE)

/*
** Common type for all collectable objects
*/
typedef struct GCObject GCObject;

/*
** Common Header for all collectable objects (in macro form, to be
** included in other objects)
*/
#define CommonHeader \
  GCObject *next;    \
  lu_byte tt;        \
  lu_byte marked

/*
** Common type has only the common header
*/
struct GCObject
{
  CommonHeader;
};

/*
** Tagged Values. This is the basic representation of values in Lua,
** an actual value plus a tag with its type.
*/

/*
** Union of all Lua values
*/
typedef union Value {
  GCObject *gc;    /* collectable objects */
  void *p;         /* light userdata */
  int b;           /* booleans */
  lua_CFunction f; /* light C functions */
  lua_Integer i;   /* integer numbers */
  lua_Number n;    /* float numbers */
} Value;

#define TValuefields \
  Value value_;      \
  int tt_

typedef struct lua_TValue
{
  TValuefields;
} TValue;

/* macro defining a nil value */
#define NILCONSTANT {NULL}, LUA_TNIL

#define val_(o) ((o)->value_)

/* raw type tag of a TValue */
#define rttype(o) ((o)->tt_)

/* tag with no variants (bits 0-3) */
#define novariant(x) ((x)&0x0F)

/* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */
#define ttype(o) (rttype(o) & 0x3F)

/* type tag of a TValue with no variants (bits 0-3) */
#define ttnov(o) (novariant(rttype(o)))

/* Macros to test type */
#define checktag(o, t) (rttype(o) == (t))
#define checktype(o, t) (ttnov(o) == (t))
#define ttisnumber(o) checktype((o), LUA_TNUMBER)
#define ttisfloat(o) checktag((o), LUA_TNUMFLT)
#define ttisinteger(o) checktag((o), LUA_TNUMINT)
#define ttisnil(o) checktag((o), LUA_TNIL)
#define ttisboolean(o) checktag((o), LUA_TBOOLEAN)
#define ttislightuserdata(o) checktag((o), LUA_TLIGHTUSERDATA)
#define ttisstring(o) checktype((o), LUA_TSTRING)
#define ttisshrstring(o) checktag((o), ctb(LUA_TSHRSTR))
#define ttislngstring(o) checktag((o), ctb(LUA_TLNGSTR))
#define ttistable(o) checktag((o), ctb(LUA_TTABLE))
#define ttisfunction(o) checktype(o, LUA_TFUNCTION)
#define ttisclosure(o) ((rttype(o) & 0x1F) == LUA_TFUNCTION)
#define ttisCclosure(o) checktag((o), ctb(LUA_TCCL))
#define ttisLclosure(o) checktag((o), ctb(LUA_TLCL))
#define ttislcf(o) checktag((o), LUA_TLCF)
#define ttisfulluserdata(o) checktag((o), ctb(LUA_TUSERDATA))
#define ttisthread(o) checktag((o), ctb(LUA_TTHREAD))
#define ttisdeadkey(o) checktag((o), LUA_TDEADKEY)

/* Macros to access values */
#define ivalue(o) check_exp(ttisinteger(o), val_(o).i)
#define fltvalue(o) check_exp(ttisfloat(o), val_(o).n)
#define nvalue(o) check_exp(ttisnumber(o), \
                            (ttisinteger(o) ? cast_num(ivalue(o)) : fltvalue(o)))
#define gcvalue(o) check_exp(iscollectable(o), val_(o).gc)
#define pvalue(o) check_exp(ttislightuserdata(o), val_(o).p)
#define tsvalue(o) check_exp(ttisstring(o), gco2ts(val_(o).gc))
#define uvalue(o) check_exp(ttisfulluserdata(o), gco2u(val_(o).gc))
#define clvalue(o) check_exp(ttisclosure(o), gco2cl(val_(o).gc))
#define clLvalue(o) check_exp(ttisLclosure(o), gco2lcl(val_(o).gc))
#define clCvalue(o) check_exp(ttisCclosure(o), gco2ccl(val_(o).gc))
#define fvalue(o) check_exp(ttislcf(o), val_(o).f)
#define hvalue(o) check_exp(ttistable(o), gco2t(val_(o).gc))
#define bvalue(o) check_exp(ttisboolean(o), val_(o).b)
#define thvalue(o) check_exp(ttisthread(o), gco2th(val_(o).gc))
/* a dead value may get the 'gc' field, but cannot access its contents */
#define deadvalue(o) check_exp(ttisdeadkey(o), cast(void *, val_(o).gc))

#define l_isfalse(o) (ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0))

#define iscollectable(o) (rttype(o) & BIT_ISCOLLECTABLE)

/* Macros for internal tests */
#define righttt(obj) (ttype(obj) == gcvalue(obj)->tt)

#define checkliveness(L, obj)           \
  lua_longassert(!iscollectable(obj) || \
                 (righttt(obj) && (L == NULL || !isdead(G(L), gcvalue(obj)))))

/* Macros to set values */
#define settt_(o, t) ((o)->tt_ = (t))

#define setfltvalue(obj, x)  \
  {                          \
    TValue *io = (obj);      \
    val_(io).n = (x);        \
    settt_(io, LUA_TNUMFLT); \
  }

#define chgfltvalue(obj, x)    \
  {                            \
    TValue *io = (obj);        \
    lua_assert(ttisfloat(io)); \
    val_(io).n = (x);          \
  }

#define setivalue(obj, x)    \
  {                          \
    TValue *io = (obj);      \
    val_(io).i = (x);        \
    settt_(io, LUA_TNUMINT); \
  }

#define chgivalue(obj, x)        \
  {                              \
    TValue *io = (obj);          \
    lua_assert(ttisinteger(io)); \
    val_(io).i = (x);            \
  }

#define setnilvalue(obj) settt_(obj, LUA_TNIL)

#define setfvalue(obj, x) \
  {                       \
    TValue *io = (obj);   \
    val_(io).f = (x);     \
    settt_(io, LUA_TLCF); \
  }

#define setpvalue(obj, x)           \
  {                                 \
    TValue *io = (obj);             \
    val_(io).p = (x);               \
    settt_(io, LUA_TLIGHTUSERDATA); \
  }

#define setbvalue(obj, x)     \
  {                           \
    TValue *io = (obj);       \
    val_(io).b = (x);         \
    settt_(io, LUA_TBOOLEAN); \
  }

#define setgcovalue(L, obj, x) \
  {                            \
    TValue *io = (obj);        \
    GCObject *i_g = (x);       \
    val_(io).gc = i_g;         \
    settt_(io, ctb(i_g->tt));  \
  }

#define setsvalue(L, obj, x)   \
  {                            \
    TValue *io = (obj);        \
    TString *x_ = (x);         \
    val_(io).gc = obj2gco(x_); \
    settt_(io, ctb(x_->tt));   \
    checkliveness(L, io);      \
  }

#define setuvalue(L, obj, x)        \
  {                                 \
    TValue *io = (obj);             \
    Udata *x_ = (x);                \
    val_(io).gc = obj2gco(x_);      \
    settt_(io, ctb(LUA_TUSERDATA)); \
    checkliveness(L, io);           \
  }

#define setthvalue(L, obj, x)     \
  {                               \
    TValue *io = (obj);           \
    lua_State *x_ = (x);          \
    val_(io).gc = obj2gco(x_);    \
    settt_(io, ctb(LUA_TTHREAD)); \
    checkliveness(L, io);         \
  }

#define setclLvalue(L, obj, x) \
  {                            \
    TValue *io = (obj);        \
    LClosure *x_ = (x);        \
    val_(io).gc = obj2gco(x_); \
    settt_(io, ctb(LUA_TLCL)); \
    checkliveness(L, io);      \
  }

#define setclCvalue(L, obj, x) \
  {                            \
    TValue *io = (obj);        \
    CClosure *x_ = (x);        \
    val_(io).gc = obj2gco(x_); \
    settt_(io, ctb(LUA_TCCL)); \
    checkliveness(L, io);      \
  }

#define sethvalue(L, obj, x)     \
  {                              \
    TValue *io = (obj);          \
    Table *x_ = (x);             \
    val_(io).gc = obj2gco(x_);   \
    settt_(io, ctb(LUA_TTABLE)); \
    checkliveness(L, io);        \
  }

#define setdeadvalue(obj) settt_(obj, LUA_TDEADKEY)

#define setobj(L, obj1, obj2) \
  {                           \
    TValue *io1 = (obj1);     \
    *io1 = *(obj2);           \
    (void)L;                  \
    checkliveness(L, io1);    \
  }

/*
** different types of assignments, according to destination
*/

/* from stack to (same) stack */
#define setobjs2s setobj
/* to stack (not from same stack) */
#define setobj2s setobj
#define setsvalue2s setsvalue
#define sethvalue2s sethvalue
#define setptvalue2s setptvalue
/* from table to same table */
#define setobjt2t setobj
/* to new object */
#define setobj2n setobj
#define setsvalue2n setsvalue

/* to table (define it as an expression to be used in macros) */
#define setobj2t(L, o1, o2) ((void)L, *(o1) = *(o2), checkliveness(L, (o1)))

/*
** {======================================================
** types and prototypes
** =======================================================
*/

typedef TValue *StkId; /* index to stack elements */

/*
** Header for string value; string bytes follow the end of this structure
** (aligned according to 'UTString'; see next).
*/
typedef struct TString
{
  CommonHeader;
  lu_byte extra;  /* reserved words for short strings; "has hash" for longs */
  lu_byte shrlen; /* length for short strings */
  unsigned int hash;
  union {
    size_t lnglen;         /* length for long strings */
    struct TString *hnext; /* linked list for hash table */
  } u;
} TString;

/*
** Ensures that address after this type is always fully aligned.
*/
typedef union UTString {
  L_Umaxalign dummy; /* ensures maximum alignment for strings */
  TString tsv;
} UTString;

/*
** Get the actual string (array of bytes) from a 'TString'.
** (Access to 'extra' ensures that value is really a 'TString'.)
*/
#define getstr(ts) \
  check_exp(sizeof((ts)->extra), cast(char *, (ts)) + sizeof(UTString))

/* get the actual string (array of bytes) from a Lua value */
#define svalue(o) getstr(tsvalue(o))

/* get string length from 'TString *s' */
#define tsslen(s) ((s)->tt == LUA_TSHRSTR ? (s)->shrlen : (s)->u.lnglen)

/* get string length from 'TValue *o' */
#define vslen(o) tsslen(tsvalue(o))

/*
** Header for userdata; memory area follows the end of this structure
** (aligned according to 'UUdata'; see next).
*/
typedef struct Udata
{
  CommonHeader;
  lu_byte ttuv_; /* user value's tag */
  struct Table *metatable;
  size_t len;        /* number of bytes */
  union Value user_; /* user value */
} Udata;

/*
** Ensures that address after this type is always fully aligned.
*/
typedef union UUdata {
  L_Umaxalign dummy; /* ensures maximum alignment for 'local' udata */
  Udata uv;
} UUdata;

/*
**  Get the address of memory block inside 'Udata'.
** (Access to 'ttuv_' ensures that value is really a 'Udata'.)
*/
#define getudatamem(u) \
  check_exp(sizeof((u)->ttuv_), (cast(char *, (u)) + sizeof(UUdata)))

#define setuservalue(L, u, o) \
  {                           \
    const TValue *io = (o);   \
    Udata *iu = (u);          \
    iu->user_ = io->value_;   \
    iu->ttuv_ = rttype(io);   \
    checkliveness(L, io);     \
  }

#define getuservalue(L, u, o) \
  {                           \
    TValue *io = (o);         \
    const Udata *iu = (u);    \
    io->value_ = iu->user_;   \
    settt_(io, iu->ttuv_);    \
    checkliveness(L, io);     \
  }

/*
** Description of an upvalue for function prototypes
*/
typedef struct Upvaldesc
{
  TString *name;   /* upvalue name (for debug information) */
  lu_byte instack; /* whether it is in stack (register) */
  lu_byte idx;     /* index of upvalue (in stack or in outer function's list) */
} Upvaldesc;

/*
** Description of a local variable for function prototypes
** (used for debug information)
*/
typedef struct LocVar
{
  TString *varname;
  int startpc; /* first point where variable is active */
  int endpc;   /* first point where variable is dead */
} LocVar;

/*
** Function Prototypes
*/
typedef struct Proto
{
  CommonHeader;
  lu_byte numparams; /* number of fixed parameters */
  lu_byte is_vararg;
  lu_byte maxstacksize; /* number of registers needed by this function */
  int sizeupvalues;     /* size of 'upvalues' */
  int sizek;            /* size of 'k' */
  int sizecode;
  int sizelineinfo;
  int sizep; /* size of 'p' */
  int sizelocvars;
  int linedefined;        /* debug information  */
  int lastlinedefined;    /* debug information  */
  TValue *k;              /* constants used by the function */
  Instruction *code;      /* opcodes */
  struct Proto **p;       /* functions defined inside the function */
  int *lineinfo;          /* map from opcodes to source lines (debug information) */
  LocVar *locvars;        /* information about local variables (debug information) */
  Upvaldesc *upvalues;    /* upvalue information */
  struct LClosure *cache; /* last-created closure with this prototype */
  TString *source;        /* used for debug information */
  GCObject *gclist;
} Proto;

/*
** Lua Upvalues
*/
typedef struct UpVal UpVal;

/*
** Closures
*/

#define ClosureHeader \
  CommonHeader;       \
  lu_byte nupvalues;  \
  GCObject *gclist

typedef struct CClosure
{
  ClosureHeader;
  lua_CFunction f;
  TValue upvalue[1]; /* list of upvalues */
} CClosure;

typedef struct LClosure
{
  ClosureHeader;
  struct Proto *p;
  UpVal *upvals[1]; /* list of upvalues */
} LClosure;

typedef union Closure {
  CClosure c;
  LClosure l;
} Closure;

#define isLfunction(o) ttisLclosure(o)

#define getproto(o) (clLvalue(o)->p)

/*
** Tables
*/

typedef union TKey {
  struct
  {
    TValuefields;
    int next; /* for chaining (offset for next node) */
  } nk;
  TValue tvk;
} TKey;

/* copy a value into a key without messing up field 'next' */
#define setnodekey(L, key, obj)  \
  {                              \
    TKey *k_ = (key);            \
    const TValue *io_ = (obj);   \
    k_->nk.value_ = io_->value_; \
    k_->nk.tt_ = io_->tt_;       \
    (void)L;                     \
    checkliveness(L, io_);       \
  }

typedef struct Node
{
  TValue i_val;
  TKey i_key;
} Node;

typedef struct Table
{
  CommonHeader;
  lu_byte flags;          /* 1<<p means tagmethod(p) is not present */
  lu_byte lsizenode;      /* log2 of size of 'node' array */
  unsigned int sizearray; /* size of 'array' array */
  TValue *array;          /* array part */
  Node *node;
  Node *lastfree; /* any free position is before this position */
  struct Table *metatable;
  GCObject *gclist;
} Table;

/*
** 'module' operation for hashing (size is always a power of 2)
*/
#define lmod(s, size) \
  (check_exp((size & (size - 1)) == 0, (cast(int, (s) & ((size)-1)))))

#define twoto(x) (1 << (x))
#define sizenode(t) (twoto((t)->lsizenode))

/*
** (address of) a fixed nil value
*/
#define luaO_nilobject (&luaO_nilobject_)

LUAI_DDEC const TValue luaO_nilobject_;

/* size of buffer for 'luaO_utf8esc' function */
#define UTF8BUFFSZ 8

LUAI_FUNC int luaO_int2fb(unsigned int x);
LUAI_FUNC int luaO_fb2int(int x);
LUAI_FUNC int luaO_utf8esc(char *buff, unsigned long x);
LUAI_FUNC int luaO_ceillog2(unsigned int x);
LUAI_FUNC void luaO_arith(lua_State *L, int op, const TValue *p1,
                          const TValue *p2, TValue *res);
LUAI_FUNC size_t luaO_str2num(const char *s, TValue *o);
LUAI_FUNC int luaO_hexavalue(int c);
LUAI_FUNC void luaO_tostring(lua_State *L, StkId obj);
LUAI_FUNC const char *luaO_pushvfstring(lua_State *L, const char *fmt,
                                        va_list argp);
LUAI_FUNC const char *luaO_pushfstring(lua_State *L, const char *fmt, ...);
LUAI_FUNC void luaO_chunkid(char *out, const char *source, size_t len);

#endif
